Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to determine when you can plant watercress by referring to the USDA zone info for Danbury.

Planting Calendar for Watercress

Frost tolerance for watercress:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Watercress can survive in some cold which means that you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant watercress in Danbury is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant watercress and expect a good harvest is probably August. If you wait any later than that and your watercress may not have a chance to fully mature. If you are starting your watercress indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Danbury. It might get as low as -5°F during the coldest months of winter.

Since the USDA zone info for Danbury is an average the actual date of last frost changes from year to year. Since half of the time in Danbury you get surprised by a frost after April 15 be ready to cover your watercress in the event of one of those late frosts.

USDA Zone Info for Danbury

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Danbury

You may be interested in your other planting guides for Danbury.